The invention applies to a tire for vehicles and a procedure for its manufacture.
It is known that most vehicles today use the so-called belted tire, whose usual method of construction is a casing with radially-, that is, perpendicular to the tire circumference, running cord threads and a belt with many, mostly crosswise-arranged, cords situated between the casing and tread.
A principal requirement of tire construction is the concurrent attainment of enough of both the transverse as well as the longitudinal stability of the tire in the appropriate proportions, as these factors decisively determine the characteristics of the driving dynamics. The well-known belted tires fulfill these specifications to a large degree.
However, today, in addition to the requirements for the best-possible handling, there is an increase in criteria for the economical use of energy and resources both in production and application. The energy consumption of a vehicle is influenced, not only by the air resistance and the weight of the entire vehicle, but also by tire characteristics such as weight, internal work, and rolling resistance. Moreover, it is not only cheaper and ecologically sounder to use less material in tire production, but it helps as well in the not unproblematical area of disposal.
In reference to the above-mentioned criteria, there are some burdensome disadvantages seen in the standard belted tires. The multi-layered cord fabric of the tire, together with its rubber casing, make a comparatively thick layer, which necessitates more material than would be desired. In addition, such a belt construction possesses a fundamentally insufficient rigidity in the radial direction, which impedes the formation of a symmetrical flat spot and specific load of the tire at the ground contact area. This obstacle is usually addressed using wider constructed radial tires, which produces the effect that the tire needs even more material, becomes heavier, and has increased coefficients of air resistance, internal work as well as rolling resistance.